Knee Arthritis: Robotic-Assisted Total Knee Replacement

Knee Arthritis: Robotic Assisted Total Knee Replacement

This live surgical video demonstrates a robotic-assisted total knee replacement for the treatment of knee arthritis. Robotic-assisted knee replacement relies on software to build models, plan the surgical steps, and provide real time guidance throughout the procedure. Here, we see a patient lying face up on the operating table with the right knee exposed. The surgeon has already made an incision along the front of the knee.

Here, the surgeon is cutting through soft tissue to expose the knee joint. The patella and soft tissues are moved to the side. Before attaching the sensors, called arrays, a pin guide is used to place 2 pins into the femur, or thigh bone. Next, 2 pins are placed directly into the tibia or shin bone. The femur, or "F", array and tibia, or "T", array are secured to the pins, and the surgeon moves the leg around so that the camera registers their positions in space.

Next, the surgeon begins the surface mapping process. A probe-tip sensor is used to locate bony landmarks. Then the surgeon traces the surface regions of the femur. This is repeated for the tibia. The robotic system records this data to build a 3D model of the patient's anatomy.

Next, a robotic device that measures knee stability is placed in the tibia. The paddles of the device apply a constant force to the inner and outer sides of the femur, and the surgeon brings the knee through the full range of motion. The robotic system records any changes in tension, indicating changes to knee stability. The robotic system compiles this data and creates a visual model of implant positioning and alignment. The surgeon adjusts the surgical plan as needed.

When the plan is finalized, the surgeon returns to the patient. Another robotic device is secured to the femur. This device moves the cutting guide to the angle selected in the surgical plan. The surgeon uses a bone saw to cut at the specific angle. Another array labeled with a "V" is used to validate that the bone cut matches the surgical plan.

The surgeon continues with a series of angled cuts around the femur, creating a precise shape that allows the implant to fit securely onto the bone. The robotic device moves to place the cutting guide on the tibia, and the surgeon continues making the appropriate bone cuts. Trial implants are placed, and the device that measures stability is inserted again. If the planned position is stable, the final implants are placed accordingly.

All incisions are closed, bandages are applied and the procedure is now complete. Here are x-rays showing the positioning of the final metal and plastic implants.